Dear Listmembers,

we´re running an Europa 20-20 MS in CF-mode for analyses of O-isotopes.
The MS itself produces a noise signal in the range of 0.05-0.1 permil
(18O). However, I always observe a drift over 3-4 hours in the range of
1-2 permil. The drift is pretty linear an can be well fitted. The 1sigma
error of drift corrected analyse of 0.3 mg silicate is between 0.12
permil. Does anybody works with such a machine and observes this drift?
Another problem is the poor (unfortiunalety MS-Windows-based) Europa
software ("vanca-sl 1.99" and especially "ancrepro" evaluation
software). If there is anybody having problems with calculation the
results using the ancrepro-programm, he may send a mail to me. I´ve
written a small programm (in C, which I can compile for MS-Windows and
Linux) for the evaluation of the raw data. It produces an *csv-file
which can be read in Excel or StarOffice,

Andreas


Dipl. Min. Andreas Pack
Mineralogisch-Petrologisches Institut und Museum
Poppelsdorfer Schloss
D-53115 Bonn (Germany)